morsk

/c --[[ remove rocks ]]
local function count_in(t, s)
  t[s] = (t[s] or 0) + 1
end
local counts = {}
for _,e in pairs(game.player.surface.find_entities_filtered{type = {"simple-entity"}}) do
  --[[ starts rock- , has -rock- in middle, or ends -rock ]]
  if e.name:match("^rock%-") or e.name:match("%-rock%-") or e.name:match("%-rock$") then
    count_in(counts, e.name)
    e.destroy()